Vavd regulator contamination and condensation control

ABSTRACT

Embodiments include a vacuum assisted venous drainage (VAVD) system, including a regulator valve assembly configured to facilitate application of vacuum to a reservoir; a control unit configured to control the regulator valve assembly to facilitate controlling application of the vacuum; at least one pressure sensor coupled to the reservoir and configured to obtain pressure measurements of pressure in the reservoir; a heating element configured to heat the regulator valve assembly to a target temperature; and at least one temperature sensor configured to determine a temperature of the regulator valve assembly.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.18/101,276, filed Jan. 25, 2023, which is a continuation of U.S. patentapplication Ser. No. 16/753,751, filed Apr. 3, 2020, which is a NationalStage Application of PCT/EP2017/075451, filed Oct. 6, 2017, which areherein incorporated by reference in their entirety.

TECHNICAL FIELD

The present disclosure relates to vacuum-assisted drainage devices andmethods. More specifically, the disclosure relates to vacuum assistedvenous drainage (VAVD) systems and methods.

BACKGROUND

Vacuum control in blood reservoirs may be utilized in a number ofdifferent drainage systems, perfusion systems, heart-lung machines,and/or the like. These systems may include vacuum assisted venousdrainage (VAVD) systems. A problem often encountered during operation ofVAVDs is the deterioration of vacuum regulators due to water vaporpresent in the air aspirated from the reservoir, which may createcondensation inside the valve assembly. Additionally, after use,humidity left in the regulators offers an opportunity for molds andbacteria to grow. Conventional regulators often must be disinfected withpotentially aggressive substances on a regular basis, causing potentialfurther deterioration of the regulators.

SUMMARY

Example 1 is a vacuum assisted venous drainage (VAVD) system, includinga regulator valve assembly configured to facilitate application ofvacuum to a reservoir; a control unit configured to control theregulator valve assembly to facilitate controlling application of thevacuum; at least one pressure sensor coupled to the reservoir andconfigured to obtain pressure measurements of pressure in the reservoir;a heating element configured to heat the regulator valve assembly to atarget temperature; and at least one temperature sensor configured todetermine a temperature of the regulator valve assembly.

Example 2 is the system of Example 1 wherein the control unit isconfigured to perform, using the heating element, a thermal disinfectioncycle to disinfect the regulator valve assembly.

Example 3 is the system of Example 1 or 2 wherein the control unit isconfigured to perform, using the regulator valve assembly, anoperational task, and maintain, using the heating element and duringperformance of at least a portion of the operational task, thetemperature of the regulator valve assembly at a target temperature.

Example 4 is the system of any of Examples 1-3 wherein the control unitis configured to maintain the temperature by heating the valve assemblyto a target temperature and maintaining the valve assembly at the targettemperature for a specified duration.

Example 5 is the system of any of Examples 1˜4 further including acooling element configured to cool the regulator valve assembly to acooling temperature.

Example 6 is the system of Example 5 wherein the cooling element is theheating element.

Example 7 is the system of any of Examples 1-6 wherein the heatingelement is a Peltier element.

Example 8 is the system of any of Examples 5-7 wherein the control unitis further configured to facilitate cooling the regulator valveassembly, using the cooling element, to a cooling temperature, thecooling temperature being a temperature selected to prevent condensationon inner surfaces of the valve assembly in response to contact withaspirated air.

Example 9 is the system of any of Examples 1-8 wherein the control unitis configured to facilitate maintaining the temperature by utilizing atleast one of a look-up table and a feedback control mechanism.

Example 10 is the system of Example 9 wherein the feedback controlmechanism is a proportional integral derivative (PID) algorithm.

Example 11 is a method, performed by a regulator for controlling vacuumin a reservoir to facilitate vacuum assisted venous drainage (VAVD), themethod including performing a thermal disinfection cycle, performing anoperational task, and maintaining, during performance of at least aportion of the operational task, the temperature of the regulator valveassembly at a target temperature.

Example 12 is the method of Example 11 wherein maintaining thetemperature utilizes electrical heating or a Peltier element.

Example 13 is the method of Examples 11 or 12 wherein maintaining thetemperature includes heating the valve assembly to a target temperatureand maintaining the valve assembly at the target temperature for aspecified duration.

Example 14 is the method of any of Examples 11-13 further includingfacilitating cooling the valve assembly to a cooling temperature, thecooling temperature being a temperature selected to prevent condensationon inner surfaces of the valve assembly in response to contact withaspirated air.

Example 15 is the method of any of Examples 11-14 wherein facilitatingcooling the valve assembly is performed by controlling a Peltierelement.

Example 16 is the method of any of Examples 11-15 wherein maintainingthe temperature utilizes at least one of a look-up table and a feedbackcontrol mechanism.

Example 17 is the method of Example 16 wherein the feedback controlmechanism is a proportional integral derivative (PID) algorithm.

Example 18 is the method of any of Examples 11-17 further comprisingdirectly measuring the pressure in the reservoir.

Example 19 is the method of Example 18 wherein directly measuring thepressure utilizes a sensing tube directly connected to the reservoir.

Example 20 is a vacuum assisted venous drainage (VAVD) system, includinga regulator valve assembly configured to facilitate application ofvacuum to a reservoir, a control unit configured to control theregulator valve assembly to facilitate controlling application of thevacuum, at least one pressure sensor coupled to the reservoir andconfigured to obtain pressure measurements of pressure in the reservoir,a heating element configured to heat the regulator valve assembly to atarget temperature, the heating element comprising a cooling element,and at least one temperature sensor configured to determine atemperature of the regulator valve assembly.

While multiple embodiments are disclosed, still other embodiments of thepresently disclosed subject matter will become apparent to those skilledin the art from the following detailed description, which shows anddescribes illustrative embodiments of the disclosed subject matter.Accordingly, the drawings and detailed description are to be regarded asillustrative in nature and not restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic block diagram of an illustrative vacuum assistedvenous drainage system, in accordance with embodiments of the disclosedsubject matter.

FIG. 2 is a schematic block diagram of an illustrative vacuum assistedvenous drainage regulator, in accordance with embodiments of thedisclosed subject matter.

FIG. 3 is a flow diagram depicting an illustrative method of performingvacuum assisted venous drainage, in accordance with embodiments of thedisclosed subject matter.

While the disclosed subject matter is amenable to various modificationsand alternative forms, specific embodiments have been shown by way ofexample in the drawings and are described in detail below. Theintention, however, is not to limit the subject matter disclosed hereinto the particular embodiments described. On the contrary, the disclosureis intended to cover all modifications, equivalents, and alternativesfalling within the scope of the subject matter disclosed herein, and asdefined by the appended claims.

As used herein in association with values (e.g., terms of magnitude,measurement, and/or other degrees of qualitative and/or quantitativeobservations that are used herein with respect to characteristics (e.g.,dimensions, measurements, attributes, components, etc.) and/or rangesthereof, of tangible things (e.g., products, inventory, etc.) and/orintangible things (e.g., data, electronic representations of currency,accounts, information, portions of things (e.g., percentages,fractions), calculations, data models, dynamic system models,algorithms, parameters, etc.), “about” and “approximately” may be used,interchangeably, to refer to a value, configuration, orientation, and/orother characteristic that is equal to (or the same as) the stated value,configuration, orientation, and/or other characteristic or equal to (orthe same as) a value, configuration, orientation, and/or othercharacteristic that is reasonably close to the stated value,configuration, orientation, and/or other characteristic, but that maydiffer by a reasonably small amount such as will be understood, andreadily ascertained, by individuals having ordinary skill in therelevant arts to be attributable to measurement error; differences inmeasurement and/or manufacturing equipment calibration; human error inreading and/or setting measurements; adjustments made to optimizeperformance and/or structural parameters in view of other measurements(e.g., measurements associated with other things); particularimplementation scenarios; imprecise adjustment and/or manipulation ofthings, settings, and/or measurements by a person, a computing device,and/or a machine; system tolerances; control loops; machine-learning;foreseeable variations (e.g., statistically insignificant variations,chaotic variations, system and/or model instabilities, etc.);preferences; and/or the like.

Although the term “block” may be used herein to connote differentelements illustratively employed, the term should not be interpreted asimplying any requirement of, or particular order among or between,various blocks disclosed herein. Similarly, although illustrativemethods may be represented by one or more drawings (e.g., flow diagrams,communication flows, etc.), the drawings should not be interpreted asimplying any requirement of, or particular order among or between,various steps disclosed herein. However, certain embodiments may requirecertain steps and/or certain orders between certain steps, as may beexplicitly described herein and/or as may be understood from the natureof the steps themselves (e.g., the performance of some steps may dependon the outcome of a previous step). Additionally, a “set,” “subset,” or“group” of items (e.g., inputs, algorithms, data values, etc.) mayinclude one or more items, and, similarly, a subset or subgroup of itemsmay include one or more items. A “plurality” means more than one.

As used herein, the term “based on” is not meant to be restrictive, butrather indicates that a determination, identification, prediction,calculation, and/or the like, is performed by using, at least, the termfollowing “based on” as an input. For example, predicting an outcomebased on a particular piece of information may additionally, oralternatively, base the same determination on another piece ofinformation.

DETAILED DESCRIPTION

Embodiments include a vacuum assisted venous drainage (VAVD) system thatincludes a regulator having a valve assembly and a control unit. Theregulator also includes a heating and/or cooling element(“heating/cooling element”) configured to heat and/or cool the valveassembly. The control unit controls the valve assembly and theheating/cooling element. Any number of different sensors may beconfigured to provide information to the control unit. In embodiments,the regulator may be configured to heat the valve assembly automaticallyat start-up. In embodiments, the regulator is configured to heat and/orcool its valve assembly by means of electrical heating and/or indirectlyby Peltier element. The regulator may also be configured to perform anauto-diagnosis on its systems. While facilitating operational tasks, theregulator may be configured to maintain the valve assembly at a targettemperature.

According to embodiments, the regulator may be precisely controlled witha combination of look up tables and control algorithms (e.g., controlloop feedback mechanisms such as, for example, PID algorithms), able toset and maintain the pressure in the reservoir at a level requested byan operator or other system component. The pressure may be directlymeasured in the reservoir in a redundant way, such as, for example, by asensing tube directly connected to the reservoir. The redundantmeasuring system may be configured to facilitate enabling the regulatorto automatically detect malfunctioning due to clogs, kinked tubes,and/or the like.

FIG. 1 is a schematic block diagram that depicts an illustrative vacuumassisted venous drainage (VAVD) system 100, in accordance withembodiments of the disclosed subject matter. As shown in FIG. 1 , theVAVD system 100 may be configured to facilitate moving blood from ablood source 102 (e.g., a patient, a part of a heart-lung machine, apart of a perfusion system, etc.) into a reservoir 104 via an intakeline 106 by applying a vacuum to the reservoir 104 using a vacuum source108 connected to the reservoir 104 via a vacuum line 110. In FIG. 1 ,the vacuum line 110 is attached to the vacuum port of the venousreservoir 104, connecting the venous reservoir 104 to the vacuum source108. The system includes a vacuum regulator 112 configured to facilitateapplication of a vacuum to the reservoir 104. The illustrated system 100includes a filter 114, disposed downstream of the reservoir 104 andupstream of the vacuum regulator 112, that is configured to preventfluid from passing into the vacuum regulator 112 and/or vacuum source108. In embodiments, for example, the filter 114 may be a hydrophobicfilter 114. In other embodiments, the system 100 may not include afilter 114.

The system 100 may include one or more sensors 116 associated with(e.g., disposed within, coupled to, etc.) the reservoir 104 andcommunicatively coupled, via a communication link 118. The sensor(s) 116may include one or more level sensors, one or more vacuum sensors, oneor more temperature sensors, and/or the like. In embodiments, forexample, the vacuum regulator 112 may be configured to providecontinuously adjustable control of the vacuum level in the venousreservoir 104 as measured, for example, by one or more vacuum sensors116 configured to directly measure a vacuum level of the reservoir104—that is, the vacuum sensor or sensors 116 obtain measurementsthrough a physical interface on and/or within the reservoir 104. Inembodiments, a vacuum sensor may be a sensing tube connected directly tothe reservoir so that a physical interface of the sensor 116 is exposedto an environment within the reservoir 104. The system 100 may includeother pressure sensors (e.g., along various portions of the vacuum lineand/or blood line) to provide redundant pressure measurements.

In embodiments, the communication link 118 may be, or include, a wiredlink, a wireless communication link such as, for example, a short-rangeradio link, such as Bluetooth, IEEE 802.11, a proprietary protocol,and/or the like. The term “communication link” may refer to an abilityto communicate some type of information in at least one directionbetween at least two locations, and should not be understood to belimited to a direct, persistent, or otherwise limited communicationchannel. That is, according to embodiments, the communication link 118may be a persistent communication link, an intermittent communicationlink, an ad-hoc communication link, and/or the like. The communicationlink 118 may refer to direct communications between the sensor(s) 116and the regulator 112, and/or indirect communications that travelbetween the sensor(s) 116 and the regulator 112 via at least one otherdevice (e.g., a repeater, router, hub, and/or the like). Thecommunication link 118 may facilitate uni-directional and/orbi-directional communication between the sensor(s) 116 and the regulator112.

In embodiments, the vacuum regulator 112 may be configured to providelevel control within the venous reservoir 104. For example, thereservoir 104 may be provided with one or more level sensors configuredto sense a level of blood and/or other fluid within the reservoir 104.The sensed level can be used to activate alarms at the user interfaceindicative of, for example, full reservoir, empty reservoir, low level,and/or the like. The sensed level can also be used in the closed loopfeedback control of other parts of a perfusion system which affect(and/or are affected by) the level of blood in the reservoir 104. Forexample, in embodiments portions of an arterial circuit 120, disposeddownstream of the reservoir 104, may be controlled based on sensedparameters such as, for example, pressure, level, temperature, and/orthe like.

As shown in FIG. 1 , the regulator 112 includes a control unit 122configured to control operation of a regulator valve assembly 124 and aheating/cooling element 126 that is configured to heat and/or cool thevalve assembly 124. In embodiments, for example, the heating/coolingelement 126 may include a Peltier element configured to heat and/or coolthe valve assembly 124. The regulator 112 may include any number ofdifferent types of sensors 128 configured to sense parameters such as,for example, temperature, pressure, and/or the like. In this manner, thecontrol unit 122 may be configured to control the valve assembly 124 tofacilitate controlling application of the vacuum applied to thereservoir 104.

Additionally, the control unit may be configured to control a heatingelement 126 configured to heat the regulator valve assembly 124 to atarget temperature; and at least one temperature sensor 128 configuredto determine a temperature of the regulator valve assembly to facilitatemaintenance of a target temperature. In embodiments, a targettemperature may include a specified temperature, a range oftemperatures, a threshold temperature, and/or the like. In embodiments,the control unit 122 may be configured, for example, to perform (e.g.,at start-up), using a heating element 126, a thermal disinfection cycleto disinfect the regulator valve assembly 124. In embodiments, followingthe disinfection cycle, the control unit may be configured to perform,using the regulator valve assembly, an operational task; and maintain,using the heating element and during performance of at least a portionof the operational task, the temperature of the regulator valve assemblyat a target temperature. In embodiments, the heating element 126 may beinserted into the valve assembly 124, attached to the valve assembly 124externally, be integrated with the valve assembly 124, and/or the like.In embodiments, power loss from one or more valves may be captured andused for heating the valve assembly 124.

For example, in embodiments, the control unit 122 may be configured tomaintain the temperature by heating the valve assembly 124 to a targettemperature and maintaining the valve assembly 124 at the targettemperature (or at another target temperature) for some specified periodof time. For example, in embodiments, the control unit 122 may beconfigured to maintain the temperature by heating the valve assembly 124to a target temperature of at least approximately 90 degrees Celsius;and maintaining the valve assembly 124 at the target temperature forbetween approximately two minutes and approximately 5 minutes. Inembodiments, the control unit may be configured to facilitatemaintaining the temperature by maintaining the valve assembly 124 at anoperating temperature of approximately 70 degrees Celsius. According tovarious embodiments, the target temperature may include any temperature,temperature range, and/or the like; and the specified time period formaintaining a target temperature may, likewise, include any time period.For example, in embodiments, the valve assembly 124 may be constructedof materials that can withstand higher temperatures, in which case thecontrol unit 122 may be configured to take advantage of that capabilityby heating the valve assembly 124 to higher temperatures that can behandled.

In embodiments, the control unit 122 may be configured to use a coolingelement to cool the regulator valve assembly to a cooling temperature.The cooling element may be, include, or be included in the heatingelement, and may include, in embodiments, a Peltier element. In thismanner, for example, the control unit 122 may be further configured tofacilitate cooling the regulator valve assembly 124, using the coolingelement 126, to a cooling temperature, the cooling temperature being atemperature selected to prevent condensation on inner surfaces of thevalve assembly 124 in response to contact with aspirated air. Accordingto various embodiments, the control unit 122 may be configured tofacilitate changing and/or maintaining the temperature by utilizing atleast one of a look-up table and a control mechanism such as, forexample, a PID algorithm, a PI algorithm, a fuzzy control algorithm,and/or the like.

According to embodiments, the control unit 122 may include a processingunit configured to communicate with memory to executecomputer-executable instructions stored in the memory. In embodiments,the control unit 122 may be, include, or be included in one or moreField Programmable Gate Arrays (FPGAs), one or more Programmable LogicDevices (PLDs), one or more Complex PLDs (CPLDs), one or more customApplication Specific Integrated Circuits (ASICs), one or more dedicatedprocessors (e.g., microprocessors), one or more central processing units(CPUs), software, hardware, firmware, or any combination of these and/orother components. Although the control unit 122 is referred to herein inthe singular, the control unit 122 may be implemented in multipleinstances, distributed across multiple computing devices, instantiatedwithin multiple virtual machines, and/or the like.

The system 100 may also include an I/O device 130, which may refer toone or more I/O devices 130 and may include any number of differenttypes of I/O devices such as, for example, light indicators, speakers,buttons, and/or the like. The I/O device 130 may be configured topresent information to a user and/or receive input from a user.According to embodiments, the I/O device 130 may be configured toindicate a device status (e.g., on/off, active, error, etc.), receive acommand from a user, and/or the like. In embodiments, the I/O device 130may include a touch-screen interface, an LED, and/or the like.

According to various embodiments of the disclosed subject matter, anynumber of the components depicted in FIG. 1 (e.g., the control unit 122,the I/O device 130, aspects of the communication link 118, and/or thearterial circuit 120) may be implemented on one or more computingdevices. A computing device may include any type of computing devicesuitable for implementing aspects of embodiments of the disclosedsubject matter. Examples of computing devices include specializedcomputing devices or general-purpose computing devices such“workstations,” “servers,” “laptops,” “desktops,” “tablet computers,”“hand-held devices,” “portable sampling devices,” and the like, all ofwhich are contemplated within the scope of FIG. 1 , with reference tovarious components of the system 100.

In embodiments, a computing device includes a bus that, directly and/orindirectly, couples the following devices: a processing unit, a memory,an input/output (I/O) port, an I/O component, and a power supply. Anynumber of additional components, different components, and/orcombinations of components may also be included in the computing device.The I/O component may include a presentation component configured topresent information to a user such as, for example, a display device, aspeaker, a printing device, and/or the like, and/or an input componentsuch as, for example, a microphone, a joystick, a satellite dish, ascanner, a printer, a wireless device, a keyboard, a pen, a voice inputdevice, a touch input device, a touch-screen device, an interactivedisplay device, a mouse, and/or the like.

The bus represents what may be one or more busses (such as, for example,an address bus, data bus, or combination thereof). Similarly, inembodiments, the computing device may include a number of processingunits, a number of memory components, a number of I/O ports, a number ofI/O components, and/or a number of power supplies. Additionally anynumber of these components, or combinations thereof, may be distributedand/or duplicated across a number of computing devices.

In embodiments, the memory includes computer-readable media in the formof volatile and/or nonvolatile memory and may be removable,nonremovable, or a combination thereof. Media examples include RandomAccess Memory (RAM); Read Only Memory (ROM); Electronically ErasableProgrammable Read Only Memory (EEPROM); flash memory; optical orholographic media; magnetic cassettes, magnetic tape, magnetic diskstorage or other magnetic storage devices; data transmissions; and/orany other medium that can be used to store information and can beaccessed by a computing device such as, for example, quantum statememory, and/or the like. In embodiments, the memory storescomputer-executable instructions for causing the processor to implementaspects of embodiments of system components discussed herein and/or toperform aspects of embodiments of methods and procedures discussedherein.

The computer-executable instructions may include, for example, computercode, machine-useable instructions, and the like such as, for example,program components capable of being executed by one or more processorsassociated with the computing device. Program components may beprogrammed using any number of different programming environments,including various languages, development kits, frameworks, and/or thelike. Some or all of the functionality contemplated herein may also, oralternatively, be implemented in hardware and/or firmware

The illustrative VAVD system 100 shown in FIG. 1 is not intended tosuggest any limitation as to the scope of use or functionality ofembodiments of the present disclosure. The illustrative system 100 alsoshould not be interpreted as having any dependency or requirementrelated to any single component or combination of components illustratedtherein. Additionally, various components depicted in FIG. 1 may be, inembodiments, integrated with various ones of the other componentsdepicted therein (and/or components not illustrated), all of which areconsidered to be within the ambit of the present disclosure.

FIG. 2 is a schematic block diagram depicting an illustrative vacuumregulator 200, in accordance with embodiments of the disclosed subjectmatter. In the diagram, solid connectors represent the blood/vacuum lineand dashed connectors represent communication/power links. According toembodiments, the regulator 200 may be, be similar to, include, or beincluded in the regulator 112 depicted in FIG. 1 . As shown in FIG. 2 ,the regulator 200 includes a vacuum port 202 configured to facilitateapplication of vacuum to a blood reservoir (e.g, the reservoir 104depicted in FIG. 1 ); a sensor port 204 for connecting a pressure sensorthat measures pressure (e.g., vacuum level) within the reservoir to theregulator 200; an emergency valve 206 configured to facilitate aeratingthe reservoir to ambient in the event that no power is present and/or amalfunction is detected; a pressure sensor 208 configured to be able tofacilitate performing a self-diagnostic process of the regulator 200.;and an alternative connection 210 to the pressure sensor 208.

As is further shown in FIG. 2 , embodiments of the illustrativeregulator 200 include a regulator valve assembly 212 (e.g., theregulator valve assembly 124 depicted in FIG. 1 ). In embodiments, thevalve assembly 212 may include any number of different types of valvessuch as, for example, an atmospheric regulator valve 214A and/or avacuum regulator valve 216A. As shown in FIG. 2 , in embodiments, thevalves 214A and 216A may include solenoid motor valve 214B and 216B,respectively. In other embodiments, the valves 214A and 216A may includeany other mechanisms of operation. In embodiments, the valve assembly212 may be integrated with, disposed within, or otherwise associatedwith a heated valve block 220 that is heated using a heating/coolingelement 222 (e.g., the heating/cooling element 126 depicted in FIG. 1 ).A temperature sensor 224 may facilitate providing a feedback controlloop for controlling and maintaining the temperature of the valveassembly 212.

As is also shown in FIG. 2 , the regulator 200 may include a pressuresensor 226 configured to sense a level of vacuum provided by a vacuumsource 228 (e.g., the vacuum source 108 depicted in FIG. 1 ); and aunidirectional valve 230 configured to protect against erroneousconnection to a pressurized gas source. In embodiments, the regulator200 may include a relief 232 to ambient air, along with a filter 234.The regulator 200 also may include a control unit 236 configured tocontrol the valve assembly 212, the heating/cooling element 222, performautomated diagnostic process, and/or the like. The control unit 236 maybe, be similar to, include, or be included within the control unit 122depicted in FIG. 1 . Additionally, as shown in FIG. 2 , the regulator200 may include one or more redundant pressure sensors 238 configured tosense vacuum level within the reservoir, and a power supply/controlconnector 240 to heart-lung machines, perfusion systems, and/or thelike.

The illustrative regulator 200 shown in FIG. 2 is not intended tosuggest any limitation as to the scope of use or functionality ofembodiments of the present disclosure. The illustrative regulator 200also should not be interpreted as having any dependency or requirementrelated to any single component or combination of components illustratedtherein. Additionally, various components depicted in FIG. 2 may be, inembodiments, integrated with various ones of the other componentsdepicted therein (and/or components not illustrated), all of which areconsidered to be within the ambit of the present disclosure.

FIG. 3 is a flow diagram depicting an illustrative method 300, performedby a regulator for controlling vacuum in a reservoir to facilitatevacuum assisted venous drainage (VAVD). According to embodiments,aspects of the method may be performed by a regulator such as, forexample, the regulator 112 depicted in FIG. 1 and/or the regulator 200depicted in FIG. 2 . As shown in FIG. 3 , embodiments of the method 300include performing a thermal disinfection cycle (block 302). Forexample, in embodiments, a regulator may perform a thermal disinfectioncycle by causing a heating element to heat the regulator valve assemblyto a target temperature (e.g., which may include any number of differenttarget temperatures such as, for example, a temperature aboveapproximately 90 degrees Celsius) and by facilitating maintaining thetemperature of the regulator valve assembly at a target temperature fora target duration (e.g., which may be any number of different timeperiods such as, for example, between approximately three minutes andsix minutes). In embodiments, the thermal cycle may include heating thevalve assembly to a target temperature and holding that targettemperature (or another target temperature) for a specified period oftime. For example, in embodiments, the thermal heating cycle may includeheating the valve assembly to a target temperature of aboveapproximately 90 degrees Celsius and holding it at that temperature forup to 5 minutes (or more than 5 minutes, in embodiments), so as todisinfect the valve assembly by, for example, killing bacteria, mold,and/or the like. In embodiments, after the target duration elapses, theregulator may be configured to cool the regulator valve assembly to acooling temperature, the cooling temperature being a temperatureselected to prevent condensation on inner surfaces of the valve assemblyin response to contact with aspirated air.

According to embodiments, the regulator may include an emergencyshut-off system configured to prevent over-heating of the valveassembly. The emergency shut-off system may be configured to detect apotential for over-heating (e.g., based on a temperature measurementexceeding a threshold, a specified duration, etc.) and, in response todetecting that potential, alter some operation of the regulator, theheating element, the system itself, and/or the like. In embodiments, theemergency shut-off system may be a separate system, integrated with theregulator, and/or the like. For example, in embodiments, the emergencyshut-off system may include functionality built into the regulator thatis configured to facilitate safe operation thereof.

In embodiments, the regulator may be configured to perform the thermaldisinfection cycle automatically at start-up. Embodiments of the method300 also include performing a self-diagnosis process (304), which may beperformed automatically at start-up (before, during, or after thethermal disinfection cycle). As is further shown in FIG. 3 , the method300 may include performing an operational task 306 and maintaining,during performance of at least a portion of the operational task, thetemperature of the regulator valve assembly at a target temperature(block 308). In embodiments, performing the operational task mayinclude, for example, applying a vacuum to a blood (e.g., venous)reservoir and controlling a valve assembly to control the appliedvacuum. In embodiments, therefore, the method may further includedirectly measuring the pressure in the reservoir, where directlymeasuring the pressure includes utilizing a sensing tube directlyconnected to the reservoir.

According to embodiments, the regulator may utilize a heating/coolingelement to facilitate control of the temperature of the valve assembly.For example, in embodiments, a valve assembly temperature ofapproximately 70 degrees Celsius can be constantly maintained, forexample, to kill bacteria and/or prevent condensation throughout theoperational task to facilitate maintenance of dry inner surfaces of thevalve assembly. The control unit may be configured to utilize at leastone of a look-up table and a control mechanism (e.g., a feedback controlalgorithm, etc.) to facilitate maintaining the temperature of the valveassembly at a target temperature. Embodiments of the method 300 mayfurther include facilitating cooling the valve assembly to a coolingtemperature, the cooling temperature being a temperature selected toprevent condensation on inner surfaces of the valve assembly in responseto contact with aspirated air. In embodiments, heating, cooling, and/ormaintaining the temperature of the valve assembly may include utilizingelectrical heating and/or a Peltier element.

Various modifications and additions can be made to the exemplaryembodiments discussed without departing from the scope of the presentdisclosure. For example, while the embodiments described above refer toparticular features, the scope of this disclosure also includesembodiments having different combinations of features and embodimentsthat do not include all of the described features. Accordingly, thescope of the present disclosure is intended to embrace all suchalternatives, modifications, and variations as fall within the scope ofthe claims, together with all equivalents thereof.

1. A method, performed by a controller for controlling vacuum in areservoir to facilitate vacuum assisted venous drainage, the methodcomprising: performing a thermal disinfection cycle by heating a valveassembly to a target temperature; performing an operational task; andmaintaining, during performance of at least a portion of the operationaltask, a temperature of the valve assembly at the target temperature. 2.The method of claim 1, wherein maintaining the temperature comprisesutilizing electrical heating or a Peltier element.
 3. The method ofclaim 1, wherein maintaining the temperature comprises: heating thevalve assembly to the target temperature; and maintaining the valveassembly at the target temperature for a specified duration.
 4. Themethod of claim 1, further comprising: facilitating cooling the valveassembly to a cooling temperature, the cooling temperature being atemperature selected to prevent condensation on inner surfaces of thevalve assembly in response to contact with aspirated air.
 5. The methodof claim 4, wherein facilitating cooling the valve assembly comprisescontrolling a Peltier element.
 6. The method of claim 1, whereinmaintaining the temperature comprises utilizing at least one of alook-up table and a feedback control mechanism.
 7. The method of claim6, wherein the feedback control mechanism comprises a proportionalintegral derivative algorithm.
 8. The method of claim 1, furthercomprising directly measuring the pressure in the reservoir.
 9. A methodof controlling a vacuum assisted venous drainage system, the methodcomprising: initiating a thermal disinfection cycle of a valve assemblyusing a controller, initiating the thermal disinfection cycle includingheating the valve assembly to a target temperature; and maintaining atemperature of the valve assembly at the target temperature for aspecified duration while performing an operational task with the vacuumassisted venous drainage system.
 10. The method of claim 9, wherein theoperational task includes applying a vacuum to a blood reservoir of thevacuum assisted venous drainage system.
 11. The method of claim 9,wherein the controller initiates the thermal disinfection cycle during astart-up procedure of the vacuum assisted venous drainage system. 12.The method of claim 9, further comprising: providing the temperature ofthe valve assembly to the controller with a temperature sensor duringthe thermal disinfection cycle.
 13. The method of claim 9, wherein afterthe specified duration, the controller initiates cooling the valveassembly to a cooling temperature, the cooling temperature being atemperature selected to prevent condensation on inner surfaces of thevalve assembly.
 14. The method of claim 9, wherein the targettemperature is 90 degrees C. or more.
 15. The method of claim 14,wherein the specified duration is 5 minutes or more.
 16. A method ofcontrolling a vacuum assisted venous drainage system, the methodcomprising: initiating a thermal disinfection cycle of a valve assemblyof a vacuum regulator using a controller during a start-up procedure ofthe vacuum assisted venous drainage system, wherein initiating thethermal disinfection cycle includes heating the valve assembly to atarget temperature for a specified duration; and applying a vacuum tothe vacuum regulator during the thermal disinfection cycle.
 17. Themethod of claim 16, further comprising: initiating cooling the valveassembly to a cooling temperature using the controller upon completionof the thermal disinfection cycle, the cooling temperature being atemperature selected to prevent condensation on inner surfaces of thevalve assembly.
 18. The method of claim 16, further comprising:providing a temperature of the valve assembly to the controller with atemperature sensor during the thermal disinfection cycle.
 19. The methodof claim 16, wherein the target temperature is 90 degrees C. or more.20. The method of claim 19, wherein the specified duration is 5 minutesor more.